(19)

(11)

EP 2 203 621 A2

(12)

(88) Date of publication A3: 04.06.2009 (43) Date of publication: 07.07.2010 Bulletin 2010/27 (21) Application number: 08837105.9 (22) Date of filing: 30.09.2008

(51) International Patent Classification (IPC):  E21B 17/02(2006.01) E21B 49/10(2006.01) E21B 17/18(2006.01) (86) International application number: PCT/US2008/078312 (87) International publication number: WO 2009/048768 (16.04.2009 Gazette 2009/16)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR Designated Extension States: AL BA MK RS (30) Priority: 09.10.2007 US 869491 (71) Applicants: Schlumberger Technology B.V. 2514 JG The Hague (NL) BG CZ DE DK GR HU IE IT LT NO PL RO SI SK TR  PRAD Research And Development Limited Road Town, Tortola (VG) Services Pétroliers Schlumberger 75007 Paris (FR) FR  Schlumberger Holdings Limited Roadtown, Tortola (VG) GB NL

(72) Inventor: PARTOUCHE, Ashers Richmond TX 77469 (US) (74) Representative: Stoole, Brian David  Sensa Gamma House, Enterprise Road Southampton Science Park Southampton Hampshire SO16 7NS Southampton Hampshire SO16 7NS (GB)